Certain off-road vehicles, such as agricultural vehicles (e.g., harvesters, combines, tractors, etc.), industrial vehicles such as construction vehicles (e.g., loaders, bulldozers, excavators, etc.) and forestry vehicles (e.g., feller-bunchers, tree chippers, knuckleboom loaders, etc.), and military vehicles (e.g., combat engineering vehicles (CEVs), etc.) to name a few, may be equipped with elastomeric endless tracks which enhance their traction and floatation on soft, slippery and/or irregular grounds (e.g., soil, mud, sand, ice, snow, etc.) on which they operate.
Typically, a track assembly of a tracked vehicle comprises a plurality of wheels and an endless track disposed around these wheels. The wheels include a drive wheel to impart motion to the endless track and one or more idler wheels to support part of the vehicle's weight on the ground via the track, guide the track as it is driven by the drive wheel, and/or tension the track.
The wheels of a track assembly are often subject to friction, impacts and/or other loads that can affect their performance, the performance of the endless track, and/or the performance of the track assembly as a whole.
For example, an idler wheel of the track assembly may be a roller wheel that rolls on an inner side of the track along a bottom run of the track to apply it on the ground. The roller wheel is often located between frontmost and rearmost ones of the wheels of the track assembly. In certain types of work vehicles such as agricultural or construction vehicles, the roller wheel is sometimes referred to as a “mid-roller”. Contact between the roller wheel and a rolling path of the track's inner side may create friction that generates some rolling resistance. Also, in some cases, the track's inner side may comprise a plurality of inner projections, referred to as inner “lugs”, which are used to drive and/or guide the track and which may contact the roller wheel as the track is in motion. Contact between the roller wheel and a drive/guide lug creates friction that may be undesirable. For example, in some situations, such friction, if too great, may lead to wear of the drive/guide lug and/or the roller wheel at an unacceptable rate. In some circumstances, the roller wheel may also be exposed to hard objects (e.g., rocks, metal pieces, etc.) lying on the ground which may impact and/or get stuck against the roller wheel and inflict abrasive damage.
For these and other reasons, there is a need for improving track assemblies of off-road vehicles.